1. Field of the Invention
The present invention relates generally to the field of actuators for an electronic device, and more specifically to an integral actuator for connecting a printed circuit board to an external circuit board.
2. Related Art
Traditional mechanisms for providing a physical and electrical connection between a printed circuit board and a motherboard use standard connectors, such as card edge connectors or pin-in-socket connectors. For the electrical connection, the printed circuit board connectors slide into corresponding connector receptacles in the motherboard. For the physical connection, there is a tight fit between the housing of the connector in the printed circuit board and the slot structure of the connector receptacle on the motherboard.
These systems have had numerous problems. One problem is the occurrence of signal delay caused by impedance mismatch between the printed circuit board and the connector, which causes overlapped and lost signals. To overcome the problem, more recent systems employ a compression connector that incorporates a flex circuit. Arrays of contact pads on the compression connector are pressed against corresponding contact pads on the motherboard. Mounting screws are used to secure the compression connector to the printed circuit board. However, the use of mounting screws is disadvantageous. For the mounting screws to be accessible to a customer installing the printed circuit board, the mounting screws must typically have lengths equal to the entire length of the circuit board. This is because the customer accesses the printed circuit board at the opposite end from where the board mounts to the motherboard. Typical mounting screw lengths are ten inches or longer. The mounting screws take up precious room on the printed circuit board, room that could be used for circuit components. Even if the mounting screws are mounted at the edges of the board, to reduce the room they waste, it is still a chore for a customer to screw in these long screws.
Because the mounting screws are typically made of metal, they provide additional problems. They can act as antennas, radiating electromagnetic energy through the board bulkhead (which is the customer interface) and outside of the board. They can also capture static electricity from customers, and pass it onto the circuit components.
Recent advances have attempted to combine flex based compression connectors with traditional card edge and pin-in-socket connectors, because of the higher costs associated with the flex based compression connectors. Traditional connectors require a significant force to insert or withdraw the connectors, but require little force to maintain the connection. On the other hand, flex based compression connectors require little force to insert or withdraw the connectors, but require a significant force to maintain the connection. In addition, flex based compression connectors allow little deviation in the position of the connectors with respect to the corresponding connectors on the motherboard. Accordingly, these systems require a sufficient force to insert or withdraw the connectors, proper alignment between the connectors and the corresponding connectors on the motherboard, and finally sufficient force to maintain the connection.